Obayashi ACBS (Automatic Constructions Building System)

In the Obayashi ACBS (Automatic Constructions Building System) (Figure 57.29), once a story has been finished, the whole support structure, which rests on four columns, is pushed upwards by hydraulic presses to the next story over a 1.5 h period. Fully extended, the support structure is 25 m high; retracted it measures 4.5 m. Once everything has been moved up, work starts on the next story. By constructing the topmost story of the high-rise building as the roof at the beginning of the building process, the site is closed off in all directions, considerably reducing the effect of the weather and any damage it might cause.